Tests, Docs and Changelog

test/libsolidity/syntaxTests/array/function_mapping.sol

@@ -0,0 +1,8 @@
+pragma experimental ABIEncoderV2;
+
+contract Test {
+    function f(mapping(uint => uint)[] memory x) public pure {}
+}
+// ----
+// TypeError 4103: (66-98): Types containing (nested) mappings can only be parameters or return variables of internal or library functions.
+// TypeError 4061: (66-98): Type mapping(uint256 => uint256)[] is only valid in storage because it contains a (nested) mapping.

test/libsolidity/syntaxTests/array/function_mapping_library.sol

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+pragma experimental ABIEncoderV2;
+library L {
+    function f(mapping(uint => uint)[2] memory a) external pure returns (mapping(uint => uint)[2] memory) {}
+}
+// ----
+// TypeError 4061: (61-94): Type mapping(uint256 => uint256)[2] is only valid in storage because it contains a (nested) mapping.